In bulk orders, sometimes the coin in the capsule and plastic pocket come separate from the cardboard holder / COA - so you'd have to pair them up yourself.
It would seem whoever sent it to you was being a bit sloppy and paired it up with the wrong COA.
The $25 came out at about the same time, and both coins are the same size (7.96g)
For a first year of issue piece, trial would be more of a possibility. For most dates, lead composition would generally suggest a relatively contemporary counterfeit.
It'd be very neat to run an XRF test or assay on that to see what the composition turns out to be - it seems quite interesting indeed.
Not to derail the topic, but something related would be 19th C. counterfeits of silver coins (i.e. US silver dollar) in PT.
Shows are a great place to meet dealers who you might not otherwise bump into, and a great experience for being exposed to things you may not have otherwise considered - excellent experiences for that alone.
Most of the $2's I've seen of late were 2003 and 2009 series. Some 2003A, 1995, and 1976 floating around, and once in a blue moon I'll see a 2013 series. I like getting them to spend - I've love to see people get more accustomed to them.
There's a lot of variables, but you can always feel free to post pictures and details and we'll try to help as best we can.
Most CGU (Chinese "Customs Gold Units") notes, though dated 1930, are actually from the 1940s and are relatively common.
All three are Roman.
I don't have a reference handy so here's some quick guesses
1) Constans /Fel Temp Reparatio type with Emperor and Victory at Prow of Ship c. 350 AD or so
2) Mid 300s sometime. Looks like a VOT X MLVT... type that lots of emperors issued
3) Radiate (Antonianius) coin, later 200s. Reverse would be standing figure w/ cornucopia.